She was the real-life Peggy of “Mad Men,” the Queen of Madison Avenue, the woman who turned staid, safe airline advertising into “Coffee, tea or me?”

Before Mary Wells Lawrence, typical ads for Pan Am or Continental simply displayed a 707. At the outset of commercial air travel, circa 1958, the jet itself was the exciting and exotic hook. And if ads showed stewardesses at all, it was to line them up in wholesome, military formation to convey the surety of passenger safety.

Wells Lawrence laughs with coworkers in the offices of her firm, Wells, Rich, and Greene Associates, in 1966.Photo: Getty Images

But as the industry grew, the non-Pan Am’s of air travel needed a hook. Enter Lawrence, whose vision was to sex up the skies. Her print and TV campaign “Air Strip” for Braniff Airlines went like this: Get out of those bundled-up New York winters and loosen up in Acapulco, Rio and Buenos Aires — complete with a stewardess stripping off a hat, scarf, coat and still more layers down to a form-fitting, come-hither dress. If the FCC would have allowed it at the time, no doubt the ad would have ended with a bikini.

“Braniff’s target customers were business fliers, which meant mostly men in the 1950s and ’60s, and most were sexist pigs,” said William Stadiem, author of “Jet Set,” a new look at commercial aviation’s early years.

A Braniff Airline hostess in 1965 with new uniforms designed by Emilio Pucci.Photo: Corbis

“Earlier ads were square, very prim and Eisenhower, a country club in the air,” Stadiem told The Post. “But here was Braniff flying to Acapulco, which was sexy and liberated. This was the time of Sinatra, ‘Come Fly With Me,’ getaways to Mexico. South of the border was naughty.”

Lawrence wanted to bait businessmen to Braniff, once a third-rate airline based out of Dallas. Braniff would be the Playboy Club of the skies (in fact, Playboy magazine featured a spread with former Braniff flight attendants decades later, in 1982, after the company went under amid industry-wide struggles).

Braniff was selling the “mile-high club,” or at least some kind of burlesque show at 30,000 feet.

“Businessmen suddenly began inventing excuses to fly down to South America,” Stadiem writes, adding that meanwhile, “the most they got was a flash of betighted thigh. Still, the fix was in, and America’s sexist corporate pigs made Braniff ‘their’ airline.”

Lawrence, who was married to a Braniff executive, also had free rein to jazz up the décor of the planes’ interiors — liven up the traditional “greige,” as she called it — and to hire designer Emilio Pucci for new in-flight uniforms. Braniff’s stewardesses came to be known as “Pucci Galores,” with the James Bond reference only further solidifying the libidinous mythology of the airline.

Braniff International Airline hostesses in 1971.Photo: AP

“She liked selling sex because she was not offended by sex,” said Stadiem. “Like [Cosmopolitan magazine editor] Helen Gurley Brown, she had no problem with a woman using sex to get ahead.”

Born in 1928 in industrial Youngstown, Ohio, Mary Wells initially set out to New York to study acting. It wasn’t to be, but her performance skills no doubt later helped in pitching to clients. She rose from the ad department at Macy’s to various “Mad Men” agencies, eventually settling at red-hot Doyle Dane Bernbach.

One client was the French tourism authority, and with DDB’s more senior copywriters focused on the glamour of Paris, Wells was left with the provinces. So, in essence, she invented the icon of the beret-topped and baguette-toting Frenchman peddling a bicycle. Suddenly, trips to the French countryside boomed.

Braniff hostesses also wore a unique plexiglass bubble to shield her from the wind and rain.Photo: Corbis

Moving on to a loftier position at Jack Tinker Associates, she produced “Plop, plop, fizz, fizz” for Alka-Seltzer, whose ads won her a Clio.

Yet it was her sexpots-in-the-sky campaign for Braniff that was most daring and revolutionary work — even if perhaps, with hindsight, its benefit to women’s liberation is debatable. “It was the late ’60s,” Stadiem said. “The mini-skirt had hit in England, the Beatles had come to America. The world was getting sexier. Mary Wells Lawrence took it and ran with it . . . and flew with it.”